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1.
J Toxicol Sci ; 45(8): 411-422, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32741894

RESUMO

Lanthanum oxide (La2O3) nanoparticles (NPs) have been widely used in photoelectric and catalytic applications. However, their exposure and reproductive toxicity is unknown. In this study, the effect of the intragastric administration of two different-sized La2O3 particles in the testes of mice for 60 days was investigated. Although the body weight of mice treated or not treated with La2O3 NPs was not different and La2O3 NPs were distributed in the organs including the testis, liver, kidney, spleen, heart and brain. La2O3 NPs accumulate more than micro-sized La2O3 (MPs) in mice testes. The histopathological evaluation showed that moderate reproductive toxicity induced by La2O3 NPs in the testicle tissues. Furthermore, increased MDA, 8-OHdG levels and decreased SOD activities were detected in the La2O3 NP-treated groups. Moreover, qRT-PCR and western blotting data indicated that La2O3 NPs affecting the blood-testis barrier (BTB)-related genes in mice testes. Taken together, these findings suggested that La2O3 NPs activated inflammation responses and cross the BTB in the murine testes. This study provided useful information for risk analysis and regulation of La2O3 NPs by administrative agencies.


Assuntos
Lantânio/administração & dosagem , Lantânio/toxicidade , Nanopartículas Metálicas/toxicidade , Óxidos/administração & dosagem , Óxidos/toxicidade , Tamanho da Partícula , Reprodução/efeitos dos fármacos , Testículo/efeitos dos fármacos , Administração Oral , Animais , Barreira Hematotesticular/metabolismo , Desoxiadenosinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Inflamação , Lantânio/metabolismo , Masculino , Malondialdeído/metabolismo , Nanopartículas Metálicas/administração & dosagem , Camundongos , Óxidos/metabolismo , Superóxido Dismutase/metabolismo , Testículo/metabolismo , Distribuição Tecidual
2.
Int J Nanomedicine ; 15: 3415-3431, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32523341

RESUMO

Purpose: Lanthanum oxide (La2O3) nanoparticles (NPs) have been widely used in catalytic and photoelectric applications, but the reproductive toxicity is still unclear. This study evaluated the reproductive toxicity of two different-sized La2O3 particles in the testes. Materials and Methods: Fifty Kunming mice were randomly divided into five groups. Mice were treated with La2O3 NPs by repeated intragastric administration for 90 days (control, nano-sized with 5, 10, 50 mg/kg BW and micro-sized with 50 mg/kg BW). Mice in the control group were treated with de-ionised water without La2O3 NPs. Sperm parameters, testicular histopathology, TEM assessment, hormone assay and nuclear factor erythroid 2-related factor 2 (Nrf-2) pathway were performed and evaluated. Results: The body weight of mice treated with La2O3 NPs or not had no difference; sperm parameters and histological assessment showed that La2O3 NPs could induce reproductive toxicity in the testicle. Serum testosterone and gonadotropin-releasing hormone (GnRH) in the NH (nano-sized with 50 mg/kg BW) group were markedly decreased relative to control group, and an increase of luteinizing hormone (LH) in NH group was detected . Additionally, transmission electron microscopy revealed that the ultrastructural abnormalities induced by La2O3 NPs were more severe than La2O3 MPs in the testes. Furthermore, La2O3 NPs treatment inhibited the translocation of nuclear factor erythroid 2-related factor 2 (Nrf-2) from the cytoplasm into the nucleus as well as the expression of downstream genes NAD(P)H quinone oxidoreductase1 (NQO1), hemeoxygenase 1 (HO-1) and (glutathione peroxidase) GSH-Px, thus abrogating Nrf-2-mediated defense mechanisms against oxidative stress. Conclusions: The results of this study demonstrated that La2O3 NPs improved the spermatogenesis defects in mice. La2O3 NPs inhibited Nrf-2/ARE signaling pathway that resulted in apoptosis in the mice testes.


Assuntos
Elementos de Resposta Antioxidante/genética , Lantânio/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Nanopartículas/toxicidade , Óxidos/toxicidade , Reprodução/efeitos dos fármacos , Transdução de Sinais , Animais , Apoptose/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Inflamação/patologia , Lantânio/sangue , Masculino , Camundongos , Nanopartículas/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Óxidos/sangue , Transdução de Sinais/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia , Testículo/ultraestrutura , Testosterona/biossíntese , Testosterona/metabolismo
3.
Aquat Toxicol ; 224: 105498, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32402915

RESUMO

The current study focuses on the ecotoxicity of cobalt oxide nanoparticles (Co3O4 NPs) in the aquatic environment towards freshwater microalgae, Chlorella minutissima. The interaction of Co3O4 NPs with microalgae shows the growth suppressing effect. The 72 h EC 50 (effective concentration of a chemical having 50% of its impact) values of Co3O4 NPs for C. minutissima was 38.16 ± 1.99 mg/L. The decline in chlorophyll a content and increase in reactive oxygen species (ROS) also indicated the compromised physiological state of microalgae. An increased LDH (lactate dehydrogenase) level in treated samples suggests membrane disintegration by Co3O4 NPs. Light microscopy, scanning electron microscopy (SEM) and Energy Dispersive X-Ray-Scanning electron microscopy (EDX-SEM) further confirm cell entrapment and deposition of Co3O4 NPs on the cell surface. Cellular internalization of NPs, as shown by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES), also contributes towards the toxicity of NPs. The findings suggest the role of extracellular as well as intracellular nanoparticles (NPs) in exerting a toxic effect on the C. minutissima.


Assuntos
Chlorella/efeitos dos fármacos , Cobalto/toxicidade , Água Doce/química , Nanopartículas Metálicas/toxicidade , Microalgas/efeitos dos fármacos , Óxidos/toxicidade , Poluentes Químicos da Água/toxicidade , Chlorella/metabolismo , Clorofila A/metabolismo , Cobalto/metabolismo , Microalgas/metabolismo , Microscopia Eletrônica de Varredura , Óxidos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/metabolismo
4.
Mutat Res ; 850-851: 503149, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32247558

RESUMO

Cadmium oxide nanoparticles (CdO NPs) are among some of the most studied and industrially used metal oxide NPs. They have been widely used for industrial application, such as paint pigments and electronic devices, and medical therapeutics. With increasing use of CdO NPs and concerns for their potential adverse effects on the environment and public health, evaluation of the cytotoxicity and genotoxicity of CdO NPs becomes very important. To date, there is a limited understanding of the potential hazard brought by CdO NPs and a lack of information and research, particularly on the genotoxicity assessment of these NPs. In this study, 10 nm CdO core-PEG stabilized NPs were synthesized, characterized and used for evaluation of CdO NPs' cytotoxicity and genotoxicity. Release of cadmium ions (Cd+2) from the CdO NPs in cell culture medium, cellular uptake of the NPs, and the endotoxin content of the particles were measured prior to the toxicity assays. Cytotoxicity was evaluated using the MTS assay, ATP content detection assay, and LDH assay. Genotoxicity was assessed using the Ames test, Comet assay, micronucleus assay, and mouse lymphoma assay. The cytotoxicity of cadmium chloride (CdCl2) was also evaluated along with that of the CdO NPs. The results showed that endotoxin levels within the CdO NPs were below the limit of detection. CdO NPs induced concentration-dependent cytotoxicity in TK6 and HepG2 cells with the MTS, ATP and LDH assays. Although the genotoxicity of CdO NPs was negative in the Ames test, positive results were obtained with the micronucleus, Comet, and mouse lymphoma assays. The negative response of CdO NPs with the Ames test may be the result of unsuitability of the assay for measuring NPs, while the positive responses from other genotoxicity assays suggest that CdO NPs can induce chromosomal damage, single or double strand breaks in DNA, and mutations. The toxicity of the CdO NPs results from the NPs themselves and not from the released Cd+2, because the ions released from the NPs were minimal. These results demonstrate that CdO NPs are cytotoxic and genotoxic and provide new insights into risk assessment of CdO NPs for human exposure and environmental protection.


Assuntos
Compostos de Cádmio/toxicidade , Nanopartículas Metálicas/toxicidade , Testes de Mutagenicidade , Mutagênicos/toxicidade , Óxidos/toxicidade , Animais , Compostos de Cádmio/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/química , Camundongos , Mutagênicos/farmacologia , Óxidos/farmacologia
5.
PLoS One ; 15(3): e0230299, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32191735

RESUMO

In this review, we highlight the current advancements in the field of triplet sensitization by three-dimensional (3D) perovskite nanocrystals and bulk films. First introduced in 2017, 3D perovskite sensitized upconversion (UC) is a young fast-evolving field due to the tunability of the underlying perovskite material. By tuning the perovskite bandgap, visible-to-ultraviolet, near-infrared-to-visible or green-to-blue UC has been realized, which depicts the broad applicability of this material. As this research field is still in its infancy, we hope to stimulate the field by highlighting the advantages of these perovskite nanocrystals and bulk films, as well as shedding light onto the current drawbacks. In particular, the keywords toxicity, reproducibility and stability must be addressed prior to commercialization of the technology. If successful, photon interconversion is a means to increase the achievable efficiency of photovoltaic cells beyond its current limits by increasing the window of useable wavelengths.


Assuntos
Compostos de Cálcio/química , Engenharia , Óxidos/química , Fótons , Titânio/química , Compostos de Cálcio/toxicidade , Óxidos/toxicidade , Reprodutibilidade dos Testes , Titânio/toxicidade , Testes de Toxicidade
6.
Ann Agric Environ Med ; 27(1): 1-5, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32208572

RESUMO

Atmospheric pollution suspended in humid air is popularly known as 'smog'. It is composed of dust particles of different sizes, as well as non-metal oxides, organic compounds, and heavy metals. Exposure to harmful substances suspended in the air - apart from, for example - smoking cigarettes, one of the modifiable factors leading to the development of respiratory diseases. There are six types of substances present in the air that have a negative impact on public health and result in significant consequences: ozone, particulate matter (PM) of different diameters - PM2.5µ, PM2.5‒10 µ, PM10 µ, nitrogen dioxide, sulphur dioxide, carbon monoxide and lead. Particular attention is given to small dust particles (PM10 and PM2.5) because they can penetrate into the lower respiratory tract. Apart from describing the composition of smog and sources of air pollution, the article also discusses the impact of atmospheric pollutants on both development and aggravation of the symptoms of such respiratory tract diseases as asthma, chronic obstructive pulmonary disease, respiratory infections and lung cancer. Some of legal measures applied in different countries aimed at reducing exposure to noxious air pollutants are reviewed. The authors believe that the increased focus on risks arising from inhaling toxic air pollution may be a first step for developing systemic solutions aimed at resolving or, at least, decreasing those risks.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Doenças Respiratórias/etiologia , Smog/efeitos adversos , Poluição do Ar/legislação & jurisprudência , Exposição Ambiental , Humanos , Óxidos/toxicidade , Material Particulado/efeitos adversos , Smog/análise
7.
PLoS One ; 15(3): e0229794, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32134972

RESUMO

In soil metal ecotoxicology research, dosing is usually performed with metal salts, followed by leaching to remove excess salinity. This process also removes some metals, affecting metal mixture ratios as different metals are removed by leaching at different rates. Consequently, alternative dosing methods must be considered for fixed ratio metal mixture research. In this study three different metal mixture dosing methods (nitrate, oxide and annealed metal dosing) were examined for metal concentrations and toxicity. In the nitrate metal dosing method leaching reduced total metal retention and was affected by soil pH and cation exchange capacity (CEC). Acidic soils 3.22 (pH 3.4, CEC 8 meq/100g) and WTRS (pH 4.6, CEC 16 meq/100g) lost more than 75 and 64% of their total metals to leaching respectively while Elora (6.7 pH, CEC 21 meq/100g) and KUBC (pH 5.6, CEC 28 meq/100g) with higher pH and CEC only lost 13.6% and 12.2% total metals respectively. Metal losses were highest for Ni, Zn and Co (46.0%, 63.7% and 48.4% metal loss respectively) whereas Pb and Cu (5.6% and 20.0% metal loss respectively) were mostly retained, affecting mixture ratios. Comparatively, oxide and annealed metal dosing which do not require leaching had higher total metal concentrations, closer to nominal doses and maintained better mixture ratios (percent of nominal concentrations for the oxide metal dosing were Pb = 109.9%, Cu = 84.6%, Ni = 101.9%, Zn = 82.3% and Co = 97.8% and for the annealed metal dosing were Pb = 81.7%, Cu = 80.3%, Ni = 100.5%, Zn = 89.2% and Co = 101.3%). Relative to their total metal concentrations, nitrate metal dosing (lowest metal concentrations) was the most toxic followed by metal oxides dosing while the annealed dosing method was generally non-toxic. Due to the lack of toxicity of the annealed metals and their higher dosing effort, metal oxides, are the most appropriate of the tested dosing methods, for fixed-ratio metal mixtures studies with soil invertebrates.


Assuntos
Metais Pesados/toxicidade , Óxidos/toxicidade , Poluentes do Solo/toxicidade , Solo/química , Animais , Concentração de Íons de Hidrogênio , Invertebrados , Metais Pesados/análise , Nitratos/análise , Nitratos/toxicidade , Óxidos/análise , Reprodução/efeitos dos fármacos , Sais/análise , Sais/toxicidade , Poluentes do Solo/análise , Testes de Toxicidade/métodos
8.
Mar Environ Res ; 156: 104917, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32174337

RESUMO

Calcium oxide (CaO) is being considered as a possible treatment for both the control of echinoderm populations and the treatment against sea lice infestation in Norwegian salmon farms. CaO particles produce an exothermal reaction when in contact with water, which can cause epidermal burns and lesions to certain target organisms leading to death. The aim of the present study was to determine the effects of fine (<0.8 mm) and coarse (<2.5 mm) CaO particles to a range of marine species from different taxonomic groups: two echinoderms (Asterias ruben and Strongylocentrotus droebachiensis); two crustaceans (Carcinus maenas and Tisbe battagliai); two molluscs (Mytilus edulis and Hinia reticulata); a polychaete (Nereis pelagica); a fish (Cyclopterus sp.); and seaweed germlings (Fucus vesiculosus). Overall, the fine CaO particles were more toxic to the selected marine species than the coarse particles. Coarse CaO particle effects were only observed in four of the nine species tested (A. rubens, S. droebachiensis, N. pelagica, T. battagliai) with similar LC50 values between 207 and 268 g/m2. For the fine CaO particles, the lowest LC50 was for the epibenthic copepod (T. battagliai) at 3.14 g/m2, followed by the sea urchin (20.1 g/m2), starfish (22.2 g/m2), ragworm (29.6 g/m2), and netted dog whelk (41.9 g/m2). Lump sucker fish exhibited significant mortalities only at the highest fine CaO concentration tested (320 g/m2) and recorded an LC50 of 226 g/m2. The toxicity data were used to generate species sensitivity distributions (SSDs) for both fine and coarse CaO particles. The hazard concentrations for 5% of the species (HC5) calculated from the SSDs, based on NOEC values, for the coarse and fine particles were 35.5 and 1.5 g/m2 respectively. Using a recommended assessment factor of 5, the Predicted No Effect Concentration (PNEC) was calculated as 7.1 and 0.3 g/m2 for coarse and fine CaO particles respectively.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Compostos de Cálcio/toxicidade , Monitoramento Ambiental , Óxidos/toxicidade , Animais , Crustáceos , Equinodermos , Peixes , Mytilus edulis , Poliquetos , Medição de Risco , Alga Marinha
9.
Int J Nanomedicine ; 15: 387-400, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32021186

RESUMO

Introduction: Rare-earth nanoparticles in the environment and human body pose a potential threat to human health. Although toxic effects of rare-earth nanoparticles have been extensively studied, the effects on the early development are not well understood. In this study, we attempted to explain the toxic effects of neodymium oxide (Nd2O3) nanoparticles on early development. Methods: We added the Nd2O3 nanoparticles at different concentrations and recorded the mortality and malformation rate per 24 hrs under a microscope. The live embryos treated with Nd2O3 nanoparticles were imaged as movies and Z step lapses with a confocal microscope, and heart rates were counted for 30 s to measure the cardiac function. The live Tg (Flk1:EGFP) transgenic embryos exposed to Nd2O3 nanoparticles were observed under confocal microscope to measure the cerebrovascular development. Subsequently, we extracted the total protein for Western blot at 5 days post-fertilisation (dpf). Embryos were collected to undergo TUNEL staining for apoptosis detection. Results: Nd2O3 nanoparticles disturbed embryo development at high concentrations (>200 µg/mL). The mortality and malformation rate gradually increased in a dose-dependent manner by morphological observation, while the Nd2O3 median lethal concentration (LD50) was 203.4 µg/mL at 120 hrs post-fertilisation (hpf). Furthermore, the Nd2O3-treated embryos showed severe arrhythmia and reduced heart rate. We also observed the markedly cerebrovascular disappearance at middle concentration (100 and 200 µg/mL). The downregulated autophagy flux in brain blood vessels and increased apoptosis level in neurons might affect vessels sprouting and contribute to the vanished cerebrovascular. Conclusion: The results suggested that the embryos exposed to Nd2O3 activated the apoptosis pathway and induced toxicity and abnormal cardiac/cerebrovascular development.


Assuntos
Apoptose/efeitos dos fármacos , Anormalidades Cardiovasculares/induzido quimicamente , Nanopartículas Metálicas/toxicidade , Neodímio/toxicidade , Óxidos/toxicidade , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados , Arritmias Cardíacas/induzido quimicamente , Relação Dose-Resposta a Droga , Embrião não Mamífero/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Larva/efeitos dos fármacos , Masculino , Testes de Toxicidade , Peixe-Zebra/genética
10.
Nat Commun ; 11(1): 310, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964862

RESUMO

Regulations currently in force enable to claim that the lead content in perovskite solar cells is low enough to be safe, or no more dangerous, than other electronics also containing lead. However, the actual environmental impact of lead from perovskite is unknown. Here we show that the lead from perovskite leaking into the ground can enter plants, and consequently the food cycle, ten times more effectively than other lead contaminants already present as the result of the human activities. We further demonstrate that replacing lead with tin represents an environmentally-safer option. Our data suggest that we need to treat the lead from perovskite with exceptional care. In particular, we point out that the safety level for lead content in perovskite-based needs to be lower than other lead-containing electronics. We encourage replacing lead completely with more inert metals to deliver safe perovskite technologies.


Assuntos
Compostos de Cálcio/normas , Chumbo/normas , Mentha spicata/efeitos dos fármacos , Óxidos/normas , Poluentes do Solo/normas , Níveis Máximos Permitidos , Titânio/normas , Compostos de Cálcio/química , Compostos de Cálcio/toxicidade , Eletrônica/normas , Chumbo/toxicidade , Óxidos/química , Óxidos/toxicidade , Solo/química , Poluentes do Solo/toxicidade , Energia Solar/normas , Titânio/química , Titânio/toxicidade
11.
Nanotoxicology ; 14(3): 326-340, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31909642

RESUMO

Potential health hazards of nanomaterials on male reproductive system have received raising concerns. Even though Mn3O4 nanoparticles (Mn3O4-NPs) is highly effective in clinical diagnostic and therapeutic applications of human disease, its potential toxic effect on the male reproductive system has not been reported. In this study, the testis damage and fertility decrease of male rats were conducted to testify the experimental reproductive injury induced by Mn3O4-NPs. After repeated tail vein injection with 10 mg/kg/week Mn3O4-NPs for 0, 60 and 120 days, Mn3O4-NPs accumulated in the testes resulted in oxidative stress and disorder of normal serum sex hormones. Experiments in vivo and in vitro indicated that mitochondria-mediated cell apoptosis were triggered via oxidative stress, demonstrated by the upregulation of malondialdehyde (MDA) and the depolarization of mitochondrial membrane potential. Notably, Mn3O4-NPs significantly resulted in a reduction of the quantity/quality of sperm and finally caused astonishing fertility decrease. Our preliminary result implied that the application of Mn3O4-NPs could be a double-edged sword and careful consideration should be given to the clinical uses.


Assuntos
Fertilidade/efeitos dos fármacos , Nanopartículas/toxicidade , Óxidos/toxicidade , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Testículo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Humanos , Masculino , Compostos de Manganês/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Óxidos/química , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Testículo/metabolismo , Testículo/patologia
12.
Food Chem Toxicol ; 136: 110954, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31707033

RESUMO

Due to the growing number of applications of cadmium oxide nanoparticles (CdO NPs), there is a concern about their potential deleterious effects. The objective of our study was to investigate the effect of CdO NPs on the immune response, renal and intestine oxidative stress, blood antioxidant defence, renal fibrotic response, bone density and mineral content. Six-week-old female ICR mice were exposed to CdO NPs for 6 weeks by inhalation (particle size: 9.82 nm, mass concentration: 31.7 µg CdO/m3, total deposited dose: 0.195 µg CdO/g body weight). CdO NPs increased percentage of thymus CD3e+CD8a+ cells and moderately enhanced splenocyte proliferation and production of cytokines and chemokines. CdO NPs elevated pro-fibrotic factors (TGF-ß2, α-SMA and collagen I) in the kidney, and concentrations of AGEs in the intestine. The ratio of GSH and GSSG in blood was slightly reduced. Exposure to CdO NPs resulted in 10-fold higher Cd concentration in tibia bones. No differences were found in bone mass density, mineral content, bone area values, bone concentrations of Ca, P, Mg and Ca/P ratio. Our findings indicate stimulation of immune/inflammatory response, oxidative stress in the intestine, starting fibrotic response in kidneys and accumulation of CdO NPs in bones of mice.


Assuntos
Compostos de Cádmio/toxicidade , Fibrose/induzido quimicamente , Imunidade Celular/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Óxidos/toxicidade , Tíbia/efeitos dos fármacos , Administração por Inalação , Animais , Compostos de Cádmio/administração & dosagem , Citocinas/metabolismo , Feminino , Intestinos/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Linfonodos/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Camundongos Endogâmicos ICR , Óxidos/administração & dosagem , Baço/efeitos dos fármacos , Timo/efeitos dos fármacos
13.
Environ Toxicol Pharmacol ; 73: 103297, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731207

RESUMO

CCA (Chromium Copper Arsenate) treated wood, widely used in outdoor residential structures and playgrounds, poses considerable dangers of leaching of its components to the environment. In this study, mouse kidney samples were used to evaluate the effects of CCA, chromium trioxide (CrO3) and arsenic pentoxide (As2O5) on cell pathophysiology by flow cytometry. Samples were collected after 14, 24, 48 and 96 h of animal exposure. While Cr had no statistically significant cytostatic effects, As2O5 induced a S-phase delay in animals exposed for 24 h, and over time a G0/G1 phase blockage. The effects of CCA in S-phase were similar, but more severe than those of As2O5. Since environmental and public health hazards due to the long durability of CCA-treated wood products, these data confirm that CCA has profoundly toxic effects on cell cycle, distinct from the compounds themselves. These cytostatic effects support cell cycle dynamics as a valuable endpoint to assess the toxicity of remaining CCA-treated infrastructures, and the expected increased waste stream over the coming decades.


Assuntos
Arsênico/toxicidade , Cromo/toxicidade , Citostáticos/toxicidade , Substâncias Perigosas/toxicidade , Arseniatos/toxicidade , Arsenicais , Compostos de Cromo , Óxidos/toxicidade , Testes de Toxicidade , Madeira
14.
Chemosphere ; 242: 125192, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31677509

RESUMO

Several types of metal oxide nanoparticles (MO-NPs) are often utilized as one of the novel class of materials in the pharmaceutical industry and human health. The wide use of MO-NPs forces an enhanced understanding of their potential impact on human health and the environment. The research aims to investigate and develop a nano-QFAR (nano-quantitative feature activity relationship) model applying the quasi-SMILES such as cell line, assay, time exposition, concentration, nanoparticles size and metal oxide type for prediction of cell viability (%) of MO-NPs. The total set of 83 quasi-SMILES of MO-NPs divided into training, validation and test sets randomly three times. The statistical model results based on the balance of correlation target function (TF1) and index of ideality correlation target function (TF2) and the Monte Carlo optimization were compared. The comparison of two target function results indicated that TF2 improves the predictability of models. The significance of various eclectic features of both increase and decrease of cell viability (%) is provided. Mechanistic interpretation of significant factors for the model are proposed as well. The sufficient statistical quality of three nano-QFAR models based on TF2 reveals that the developed models can be efficiency for predictions of the cell viability (%) of MO-NPs.


Assuntos
Nanopartículas Metálicas/toxicidade , Modelos Teóricos , Relação Quantitativa Estrutura-Atividade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Modelos Estatísticos , Método de Monte Carlo , Óxidos/toxicidade
15.
Ecotoxicol Environ Saf ; 188: 109909, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31740235

RESUMO

Mn3O4 nanoparticles (NPs) are used increasingly in various fields due to their excellent physiochemical properties. Previous studies have documented that Mn-based nanomaterials resulted in excess reactive oxygen species (ROS) generation and dopamine (DA) reduction both in vivo and in vitro experiments. However, little is known about the mechanism of ROS production and DA decrease induced by Mn-based nanomaterials. The present study was carried out to elucidate the mechanism of the co-incubation model of dopaminergic neuron PC12 cells and the synthesized Mn3O4 NPs. The results demonstrated that exposure to Mn3O4 NPs reduced cell viability, increased level of lactate dehydrogenase (LDH), triggered oxidative stress and induced apoptosis. Notably, the level of ROS was remarkably increased (>10-fold) with Mn3O4 NPs exposure. We also found that mitochondrial calcium Ca2+ uniporter (MCU) was up-regulated and the mitochondrial Ca2+ concentration ([Ca2+]mito) increased induced by Mn3O4 NPs in PC12 cells. Furthermore, the MCU inhibitor RuR significantly attenuated Mn3O4 NPs-induced [Ca2+]mito, ROS production and apoptosis. In PC12 cells, the decrease of DA content was mainly due to the downregulation of DOPA decarboxylase (DDC) expression caused by Mn3O4 NPs treatment. The expression of proteins related to DA storage system was not significantly affected by treatment.


Assuntos
Apoptose/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Óxidos/toxicidade , Animais , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Sobrevivência Celular , Dopa Descarboxilase/genética , Dopa Descarboxilase/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Compostos de Manganês/química , Nanopartículas Metálicas/química , Estresse Oxidativo/efeitos dos fármacos , Óxidos/química , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismo
16.
Chemosphere ; 245: 125625, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31855754

RESUMO

Using Caenorhabditis elegans as an animal model, we compared the toxicity between nanopolystyrene and three metal oxide nanoparticles (NPs) (Al2O3-NPs, TiO2-NPs, and SiO2-NPs). After exposure from L1-larvae to adult day-1, nanopolystyrene (100 µg/L) reduced brood size and induced severe germline apoptosis, and nanopolystyrene (10-100 µg/L) decreased locomotion behavior, induced obvious reactive oxygen species (ROS) production, and activated noticeable mitochondrial unfolded protein response (mt UPR). Using several endpoints (lethality, development, reproduction, and/or locomotion behavior), we found that nanopolystyrene could induce more severe toxicity than SiO2-NPs, although nanopolystyrene did not cause the toxicity comparable to that in Al2O3-NPs or TiO2-NPs exposed nematodes. Our data will be useful for understanding the exposure risk of nanopolystyrene on environmental organisms. Moreover, the detected toxicity difference between nanopolystyrene and three metal oxide NPs were associated with the differences in both induction of oxidative stress and activation of mt UPR in exposed nematodes.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Nanopartículas/toxicidade , Óxidos/toxicidade , Poliestirenos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Locomoção/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Reprodução/efeitos dos fármacos , Resposta a Proteínas não Dobradas/efeitos dos fármacos
17.
Int J Nanomedicine ; 14: 7729-7741, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31806958

RESUMO

Background: Recently, several studies demonstrate the possible role of zinc oxide (ZnO) in the protection of several skin diseases, but less is known about the role of ZnO nanoparticles in the inflammatory skin disease. So, this study was designed to confirm the pivotal role of the nano zinc oxide cream in the alleviation of lead oxide (PbO) induced-allergic dermatitis in rats. Materials and methods: Two concentrations (1% and 6%) of ZnONPs creams were prepared and characterized prior to being used in the study. A total number of 30 male Wistar rats were randomly divided into six groups. Group 1 (negative control), groups 2&3 (either 1% or 6% ZnONPs control groups), group 4 (PbO), groups 5&6 (co-treatment of each ZnONPs concentration+PbO). All rats in different groups were observed daily to determine the severity of dermal gross lesions. Histopathological studies, mRNA analysis, and oxidative stress evaluations were performed on the affected skin tissue. Immunohistochemical studies were performed to evaluate the expression of cluster of differentiation CD4, CD8 and intercellular adhesion molecules ICAM-1 in different groups. Results: PbO caused extensive skin oxidative damage manifested by a significant increase in MDA level with a decrease in GSH content and CAT activity. The results of histopathological and immunohistochemical examinations revealed that topical application of PbO for 14 days led to severe allergic dermatitis with remarkable elevations in the number of CD4+ T-helper, CD8+ T-cytotoxic lymphocytes, and ICAM-1 expression. On the other hand, noticeable improvements were recorded in all the previous toxicopathological parameters among the groups treated by either 1% or 6% ZnO-NPs cream. However, the best results were observed in the group treated with 1% ZnO-NPs cream. Conclusion: Our findings suggest that 1% of ZnO-NPs cream is safe when applied topically on the inflamed skin. Moreover, it had anti-inflammatory and antioxidant effects so that, it is recommended to use the 1% ZnO-NPs cream to avert the dermal toxicity-induced by PbO.


Assuntos
Dermatite Alérgica de Contato/tratamento farmacológico , Chumbo/toxicidade , Nanopartículas Metálicas/uso terapêutico , Óxidos/toxicidade , Substâncias Protetoras/farmacologia , Óxido de Zinco/farmacologia , Administração Tópica , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Dermatite Alérgica de Contato/etiologia , Dermatite Alérgica de Contato/patologia , Modelos Animais de Doenças , Masculino , Malondialdeído/metabolismo , Nanopartículas Metálicas/química , Pomadas/química , Pomadas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/química , Ratos Wistar , Óxido de Zinco/administração & dosagem , Óxido de Zinco/química
18.
Biomater Sci ; 7(11): 4491-4502, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31566646

RESUMO

Here, we have compared the behavioral neurotoxicity of a manganese nanoformulation (citrate functionalized Mn3O4 nanoparticles; C-Mn3O4 NPs) with that of the well-known neurotoxicant, ionic Mn, in an animal model. We found that mice administered with C-Mn3O4 NPs showed no signs of a neurobehavioral disorder, but the NPs instead ameliorated Mn-induced neurotoxicity (Parkinson's-like syndrome) through the chelation of excess Mn ions and subsequent reduction of oxidative damage.


Assuntos
Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Nanopartículas/toxicidade , Neurônios/efeitos dos fármacos , Óxidos/toxicidade , Animais , Hipocampo/metabolismo , Hipocampo/patologia , Compostos de Manganês/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Nanopartículas/administração & dosagem , Neurônios/metabolismo , Neurônios/patologia , Oxirredução , Óxidos/administração & dosagem
19.
Ecotoxicol Environ Saf ; 185: 109733, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31580980

RESUMO

Presence of missing data points in datasets is among main challenges in handling the toxicological data for nanomaterials. As the processing of missing data is an important part of data analysis, we have introduced a read-across approach that uses a combination of supervised and unsupervised machine learning techniques to fill the missing values. A series of classification models (supervised learning) was developed to predict class label, and self-organizing map approach (unsupervised learning) was used to estimate relative distances between nanoparticles and refine results obtained during supervised learning. In this study, genotoxicity of 49 silicon and metal oxide nanoparticles in Ames and Comet tests. Collected literature data did not demonstrate significant variations related to the change of size including selected bulk materials. Genotoxicity-related features of nanomaterials were represented by ionic characteristics. General tendencies found in the current study were convincingly linked to known theories of genotoxic action at nano-level. Mechanisms of primary and secondary genotoxic effects were discussed in the context of developed models.


Assuntos
Dano ao DNA , Nanopartículas Metálicas/toxicidade , Modelos Teóricos , Mutagênicos/toxicidade , Aprendizado de Máquina não Supervisionado , Linhagem Celular , Ensaio Cometa , Humanos , Nanopartículas Metálicas/classificação , Mutagênicos/classificação , Óxidos/classificação , Óxidos/toxicidade , Relação Quantitativa Estrutura-Atividade , Salmonella typhimurium/genética
20.
Mutat Res ; 842: 146-157, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31471003

RESUMO

The genotoxicity of nanoparticles is a major concern for nano-safety appraisal in the bryophytes as they are the primary colonizers of bare land, indicators of atmospheric pollution and excellent accumulators of trace metals. The present study for the first time evince the in planta genotoxicity of MnONP in Physcomitrella patens a model plant system utilized for evolutionary developmental genetics. The induction of DNA strand breaks was confirmed by comet assay at all tested concentrations corroborated with the enhanced generation of ROS, increase in Mn dissolution, uptake and internalization. Genotoxicity is often coupled with epigenetic alterations. In the present study, global DNA methylation pattern at the level of single cells was studied by the methylation sensitive comet assay using the isochizomeric restriction endonucleases HpaII (digests unmethylated and hemimethylated DNA) and MspI (digests methylated DNA at 5'-CmCGG-3'). MnONP incited DNA hypomethylation in P. patens gametophores treated with the highest concentration of MnONP (20 µg/mL). The DNA hypomethylation incurred upon MnONP exposure was comparable with that of the DNA methylation blocker 5-azacytidine. This can be ascribed to its clastogenic potential mediated by the formation of H2O2, OH and O2¯. There are no reports on the epigenotoxicity of nanomaterials in plants utilizing the detection of DNA damage and DNA methylation. This can open up new avenues of research on the assessment of the epigenotoxic impact of environmentally relevant nanoparticles using bryophytes as model indicator plant system.


Assuntos
Bryopsida/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Mutagênicos/toxicidade , Nanopartículas/toxicidade , Óxidos/toxicidade , Ensaio Cometa/métodos , Peróxido de Hidrogênio/toxicidade , Compostos de Manganês
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